Dragon Age 2 - PC system requirements:

Minimum:
OS: Windows XP with SP3, Windows Vista with SP2, Windows 7
CPU: Intel Core 2 Duo (or equivalent) running at 1.8 GHz or greater
CPU: AMD Athlon 64 X2 (or equivalent) running at 1.8 GHz or greater
RAM: 1 GB (1.5 GB Vista and Windows 7)
Video: Radeon HD 2600 Pro 256 MB
Video: NVIDIA GeForce 7900 GS 256 MB cards
Disc Drive: DVD ROM drive required
Hard Drive: 7 GB
Sound: Direct X 9.0c Compatible Sound Card

Recommended:
CPU: Intel Core 2 Quad 2.4 GHz Processor or equivalent
CPU: AMD Phenom II X3 Triple core 2.8 GHz or equivalent
RAM: 2GB (4 GB Vista and Windows 7)
Video: ATI 3850 512 MB or greater,
Video: NVIDIA 8800GTS 512 MB or greater
DirectX 11: ATI 5850 or greater
DirectX 11: NVIDIA 460 or greater

http://dragonage.bioware.com/da2/info/faq/